Why DNS Changes Take Time to Propagate

You changed a DNS record. You loaded the site. Nothing changed. This is normal — DNS is a globally cached system, and changes take time to roll out. Here is what is happening and how to wait it out (or speed it up).

How DNS caching works

When a resolver looks up your domain, it stores the answer for as long as the record's TTL (Time To Live) says — usually 1 to 24 hours. Until that cache expires, the resolver returns the old value, regardless of what you changed at the source.

"Propagation" is just the world's resolvers gradually expiring their cached entries and querying the new value.

Typical propagation times

• Most networks: within 1 hour.
• Worldwide: within 4 to 24 hours.
• Worst case: up to 48 hours, especially on networks with aggressive caching.

Plan ahead with TTL

If you know a DNS change is coming (e.g. you are migrating hosts), lower the TTL on the affected records to 300 seconds (5 minutes) at least 24 hours in advance. After the change, wait for things to settle, then raise the TTL back to a normal value (3600 or 86400 seconds).

Check propagation

Use these tools to see what value is being served from different regions:

• dnschecker.org — visual map of DNS responses worldwide.
• dig +trace yourdomain.com — follows the resolution from root servers down.
• dig @8.8.8.8 yourdomain.com — query Google's public DNS directly.

Speed up your own browser

Browsers and operating systems have their own DNS cache. To clear yours:

• macOS: sudo dscacheutil -flushcache; sudo killall -HUP mDNSResponder
• Windows: ipconfig /flushdns
• Chrome: visit chrome://net-internals/#dns and click Clear host cache.

When something is actually wrong

If a record still has not propagated 24+ hours after the change, double-check that you edited the record at the right DNS provider — the one your domain's nameservers actually point at, not a former provider.